208 AMAX, RL 17, 16" LMT

[The Gump]

Has anyone run this combo? I would like to get more long range performance out of my LMT. I am contemplating the purchase of a .260 barrel but I would like to see if I can get this load to work first.

Yesterday I did some pressure testing. I developed my loads in .5gr increments from 46.0-51.0. The primers were on all loads were somewhat flat but consistently flat from low to high.

I'm running a 16" barrel. I hope to be able to run 2300 fps or better. If I can't achieve that velocity reliably with accuracy I'm going to go to .260 with H4350 and 142 SMK's.

This weekend I'm going to develop charges from 47.0-49.0 in .3gr increments to verify 100 yard accuracy and accuracy/trajectory at distance.

With a 16" barrel the gun is blasty to say the least.

And yes, I do realize there is a big difference in trajectory between a 208 .308 at 2300 fps and 142 .260 at 2800.

 

[CanSniper]

Re: 208 AMAX, RL 17, 16" LMT

Holy sheet!! 51 grns of rl 17 in a 308 case and it fits in the mag???

You might be better off with faster powder like varget, just my thought though.

I have wondered about the 208 in a AR as well, I would be interested to hear how it works out.

 

[Tx_Flyboy]

Re: 208 AMAX, RL 17, 16" LMT

Pete,

A gentleman that frequents this site (BCP) was able to achieve 2400fps with 2000MR powder out of this 16" 308AR...your powder choice will give you slightly faster speeds, although at the cost of increased temperature sensitivity.

You will prolly have better luck with responses by posting your question in the reloading section. There is a thread on this very issue (208AMX + RL-17) and on page 12/13, a gentleman got 2550ft/s out of a 20" gas gun at mag length.

Since you already have relaoding components for the 308, why dont you just pick up a slightly longer barrel (18-20). You will get enough velocity to be supersonic to 1200yards at sea level, and spank guys running 155s and 175 with longer tubes...this is more cost effective than picking up a new barrel, new brass, new dies, diff powder, giving up the availability of componments etc, etc just to run the 260

Good Luck and let us know how it turns out.

 

[The Gump]

Re: 208 AMAX, RL 17, 16" LMT

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CanSniper</div><div class="ubbcode-body"><span style="font-weight: bold">Holy sheet!! 51 grns of rl 17 in a 308 case and it fits in the mag??? </span>

<span style="font-weight: bold">You might be better off with faster powder like varget</span>, just my thought though.

I have wondered about the 208 in a AR as well, I would be interested to hear how it works out. </div></div>

Ya, it's pretty full. I did have my doubts.

From what I have read, Varget won't be able to push them to the same speed RL17 will.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Tx_Flyboy</div><div class="ubbcode-body">Pete,

A gentleman that frequents this site (BCP) was able to achieve 2400fps with 2000MR powder out of this 16" 308AR...your powder choice will give you slightly faster speeds, although at the cost of increased temperature sensitivity.

<span style="font-weight: bold">You will prolly have better luck with responses by posting your question in the reloading section.</span> <span style="font-weight: bold">There is a thread on this very issue (208AMX + RL-17) and on page 12/13</span>, a gentleman got 2550ft/s out of a 20" gas gun at mag length.

<span style="font-weight: bold">Since you already have relaoding components for the 308</span>, why dont you just pick up a slightly longer barrel (18-20). You will get enough velocity to be supersonic to 1200yards at sea level, and spank guys running 155s and 175 with longer tubes...this is more cost effective than picking up a new barrel, new brass, new dies, diff powder, giving up the availability of componments etc, etc just to run the 260

Good Luck and let us know how it turns out. </div></div>

Good point about the reloading section.

I went through the thread you speak of prior to posting but I don't recall seeing anything about performance with this combination from a 16" barrel.

I shoot .260 out of a bolt gun. I've got dies, 3K+ Match Kings, 1k+ pieces of brass, and 16 lbs of H4350 in the basement. I probably should have mentioned that.

I really just want to shoot my gas gun in the August PMG PRS. I don't want to buy a new barrel just to do that but if I have to I will. I figure if I'm going to get another barrel it may as well be in .260. 20" or maybe a 22''.

I will be sure to post my results.

Ryan

 

[Tx_Flyboy]

Re: 208 AMAX, RL 17, 16" LMT

Ryan,

The thread i mentioned only has a guy shooting a 20" gas gun...BCP was running an 18" 308AR at 5,000ft altitude...however, his results are in the 2000MR thread.

I did not know you also owned a .260 bolt gun along with reloading components.

Buying a new barrel just to use in a single match is a bit over the edge. Try seeing if you can make the combo work with ur 16" barrel and take it from there.

If you do decide to buy a londer barrel, y dont you go all out and get a 24" tube? You already have the 16" for short range stuff, so don't get an 18" as the velocity increse will be disappointing for the money. Rainier arms 24" Ultramatch barrel is $395, and their Select is grade is about $100 less IIRC.

I have a 20" light weight profile (.750" barrel diameter) upper in a 308 AR for hunting...and I'm building a 30" upper for F-class & Palma shooting...I expect to take advantage of every fps i have coming to me...

 

[BCP]

Re: 208 AMAX, RL 17, 16" LMT

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Tx_Flyboy</div><div class="ubbcode-body">Pete,

A gentleman that frequents this site (BCP) was able to achieve 2400fps with 2000MR powder out of this 16" 308AR...</div></div>

I'm pretty sure that was my DPMS SASS. I didn't have any luck with the 208 amax in my 16" with either varget or 2000MR.

2000MR + 175SMK is a lethal combination though. Out of my 16" it chronos 2550fps easily and is accurate.

OP, if your rifle ends up not likeing the RL17 + 208 combo try 2000MR and a 175ish bullet.

 

[Pusher591]

Re: 208 AMAX, RL 17, 16" LMT

Run some 178 Hornady bthp's hot instead of getting a new barrel is my vote.

 

[m1ajunkie]

Re: 208 AMAX, RL 17, 16" LMT

Not sure what your ultimate goal is, but I'm having great luck with the 178 amax out of my 16" MWS. The furthest hit I have made with it is 1290yds, and the furthest consistent hits have been 1098yds. This is with 44gr varget at 2460fps.

 

[The Gump]

Re: 208 AMAX, RL 17, 16" LMT

My ultimate goal is to accurately stay super sonic past 1200yds with the 208. It doesn't seem that this will be obtainable with a 16" barrel. Each charge I used would not shoot any better than 2 moa from 100 yds out to 800 yds or so. I could have been a little better on the trigger but I don't think thats the case. I was shooting my .260 out to 1150 with no problem.

This load simply doesn't want to work. I'll see if I can get my normal load (42gr Ramshot Tac/ 175SMK) to run a bit hotter. The data on it puts me at 2450. Consistent 1100 yd hits is my goal.

 

[BCP]

Re: 208 AMAX, RL 17, 16" LMT

I tried the same stuff with my 16". On paper it should be possible but I could never get it to work as well as I wanted. 3MOA with no wind and when the wind came up they were all over the damn place.

FWIW, 178 BTHP hornady win brass 47.5 2000MR 2.81COAL 2550fps was my best. So if you want something to plug in there you go.

 

[TAC308]

Re: 208 AMAX, RL 17, 16" LMT

This kind of reminds me of a a square peg and a round hole...

Keep in mind - FPS is not the end all be all on accuracy... remember OCW.

Good luck to you.

 

[The Gump]

Re: 208 AMAX, RL 17, 16" LMT

Yup, back to to drawing board. When I get back from the Cup I'll give 2000MR a shot. How does it fare in hot weather? Any pressure spikes?

 

[BCP]

Re: 208 AMAX, RL 17, 16" LMT

I shot the load I posted in the winter and summer and didn't have pressure problems. Working up from 46 might be smart though.